Busways for electrical distribution systems are commonly understood in the art to include multiple pre-assembled sections of ducts containing individually insulated, usually flat electrical conductors or busbars. The individual sections are designed to be easily connected together, both electrically and mechanically, end-to-end to form any desired length. In a plug-in busway, at least some of the sections are equipped with built-in electrical stabs adapted to receive plug-in units which are enclosures for attaching electrical devices to be connected to the busway. Such devices may include power take offs (receptacles), metering, and other branch devices typically controlled by a circuit breaker at the junction point of the branch. However, currently known plug-in units may present exposed conductor within the plug in units. During the installation process of equipment, such as circuit breakers, into the plug in unit enclosure connection of the breaker to exposed conductors may represent a safety concern for the operator or a chance for arcing which could damage the equipment. With an increasing industry emphasis on operator safety and electrical arc control, it is believed that an improved system of plug in unit assembly for busways is desirable.
Thus, a need exists for an improved way to insert and remove devices from the plug in unit enclosure, sometimes as part of a larger scheme for installing and removing branch circuit devices without deenergizing the electrical busway system. Likewise, it may be desirable to provide apparatus and methods for safely connecting a plug in unit enclosure at the busway conductor stabs in the first instance without producing significant safety or arcing hazard in addition to providing the aforementioned measures to prevent unintentional contact with live, i.e. energized, conductors within the plug in unit.